Here's the latest author behaving badly for you guys:
British author RJ Ellory has been caught not only sockpuppeting reviews, but also posting negative reviews for his rivals on Amazon. He's posted under two different names, Jelly Bean and Nicodemus Jones, if I'm understanding this correctly.
I haven't been able to find the negative review, but from what I read from the Telegraph, he gave MacBride's Dark Blood one star, saying "Unfortunately this is another in the seemingly endless parade of same-old-same-old Police procedurals that seem to abound in the UK." Now it should be noted that these are the only ones that are known. Ellory has offhandedly remarked that he'll go to forums and post under other names, so there could be more.
Now author reviews aren't automatically an evil thing. As long as they admit who they are from the get-go and don't post on sites that actively sell their work, there's nothing inherently wrong with an author reviewing their own work. It's when they do it via sockpuppets and post the reviews on places that sell their works that it becomes somewhat seedy. They're essentially trying to overly promote their own work with fake reviews and reduce sales for their rivals by posting negative ones. Ellory has given an apology, but some have questioned his sincerity.
To date, the reviews for Ellory's Jelly Bean persona are still available on Amazon UK. His Nicodemus Jones reviews have all been removed.
This is really just one example of an ongoing problem, as Ellory isn't the only author who has been caught posting fake reviews for himself. Robert Stanek is the reigning king of fakery, and that's not including the habit of many self-published or indie authors that do review swaps with other authors or get their friends and family to post positive reviews without admitting their relation to the author.
*Jellybean profile on Amazon
*Nicodemus Jones profile
*Amazon forum where Jones posts as "Roger" instead of Nicodemus
*The author caught out praising his own books on Amazon... and writing disparaging reviews of his rivals' works
*RJ Ellory: detected, crime writer who faked his own glowing reviews
*Amazon Reviews: RJ Ellory Apologises for Fakery